Electronic relay



Jan. 2, 1945. K. SCHLESINGER ELECTRONIC RELAY 'i iled May 50, 1942 2,SheetsSheet 1 llllll w a 5% .5; Qlll-k INVENTOR J ATTORNEY 2Spats-Sheet 2 K. SCHLESINGER ELECTRONIC RELAY Filed my 30, 1942 Jan. 2,1945.

kh v a h-% m v my. W .l: r In .1: v any I m M M 33 w: 90x) QMK F W m \kMw Ii- 1 b H UM Rh t hv K MK n 1 i 11 nbk Tg 3: w u I A ATTORNEYmoraines "UNITED STATES PATENT OFFICE militia...

Kurt Schlesinger, watwmm, ma, ml

to Radio Corporation tlon of Delaware of America, v a corporamuaaoam; so1942, Serial No. 445.253

(01. 111- 45) ling pulses over a wide range'oi frequencies and 1:Claims.

This invention relates to electronic apparatus and is particularlyconcerned with electronic relays and square wave generators which arecapable of operating under the control of driving impulsessupplied froman external source.

' In the prior art, many systems for producing square waves have beendescribed from time to time. Most devices of such a nature are in theform of oscillators. In many instances, some such devices of the priorart operate on the principle of the multi-vibrator and, as such, theycontinuously perform their oscillations. They are subject, however, tothe material disadvantage that they cannot be properly synchronized byinput pulses or signals, exceptover a relatively narrow range offrequency which has been found to be rather close to the natural periodof the syste Other arrangements of the prior art which have been usedfor square wave generators and electronic relays have embodied uses ofthe socalled gas filled tubes,. such as those-known by the trade nameThyratron. In many respects switchlnil circuits of this general typesatisfy many operational conditions to be expected from a relay andsquare wave generator, but they. are subject to the substantialdisadvantage that the presence of the gas filling within the switchingtubes usually leads to prematured aging of the stage which is conductiveduring the standby period in the operation.

It is, accordingly, an object of the present invention to provide anelectronic relay and square wave generator unit which is of aninherently meant the condition of operation will be of nonchangingcharacter pending the receipt of a controlling or trigger-mg" impulse.

.Further, the present invention has, as one of its aims and objects,that of providing an extremely rapid switching oi the transient in thesquare waves from the lower to the higher levels, or vice versa, whichusually occupy an extremely short period of time, for example, a timeperiod not exceeding 100 micro-secon a A further object of the inventionis to provide a circuit of the character hereinabove referred to whichembodies only high vacuum tubes and which functions with an efiiciencyat least as great as that of the gas filled tubes.

A further object of the invention is to provide a circuit of the squarewave generator and relay type which is capable of responding to controlthus capable of functioning and operating as an electronic commutatorthroughout an especially wide frequency range. i A further object of theinvention is to provide an electronic relaying and square wave genera rystem for use in co-operative relationship with a cathode rayoscilloscope so as to enable an observer of the luminescent patterntraced upon the tube to observe simultaneously two distinct transientphenomena. A further object otthe invention is to provide a relaying andsquare wave generator systemior use with cathode ray oscillographapparatus for observing multiple transientsin which the true wave formsoi theplurality of transients are shown in their entirety without anyvisible interruption because of the switchingaction and thus 5 toprovide a system wherein the switching action in its totalityoccursiollowing a predetermined completion of reproduced-transienteffects.

Further objects and advantages of the invention are those ofprovidingapparatus which overcomes one or more difllculties and defects 0! theprior art by simplified inexpensive and efliciently operating circuitinstmimentalities.

Still other objects and advantages will become apparent from a readingof the following specification and claims in connection with theaccompanying drawings, wherein Fig. 1 represents a schematicrepresentation of the circuit of a square wave generator;

Fig. 2 represents a modification oi the circuit of Fig. 1; Fig. 3represents the inclusion of a circuit of the general character shown byPig. 1 with a cathode ray oscilloscope or oscillograph for observingmultipl transients, and,

F18. 4 is a further modification of the circuit arrangement of Fig. 1.

Referring now to the drawings for a further understanding oftheinvention, it will be seen Accordingly, the

In one preferred form of the invention as it is disclosed in thisapplication, the square wave generator unit comprises a pair of vacuumtubes II and I2 which may, for instance, each be of the general typeknown in the art as the type 6N7, which are thus understood to be twintriodes, although it is obvious that separate triodes may also be used,if desired.

In the arrangement as it is disclosed by Fig. 1, the tube II will beunderstood to serve as the driver tube and the tube l2 will beunderstood to constitute the electronic relay tube. The circuit of theelectronic relay l2 resembles, in some respects, the well knownmulti-vibrator in that the plate and control electrode elements arecross connected, but, it must be noted, the use of usual capacitiveconnections is avoided.

In the preferred form of the circuit, a source of positive voltage isconnected at the terminal point [4 and supplied to the plate or anodeelements l6 and I6 of the tube l2 through the resistor elements I! andi3 by way of the conductor H, which connects intermediate the resistorsl1 and I3. Output energy from the system is derived from the terminalpoints 20 and 2| connected to the plate or anode elements l and I6respectively. Connections are made from the plate element ii of thefirst half of the relay tube l2 to the control electrode 22 of thesecond half of the tube by way of the resistor element 23, and also aconnection i made by way of the conductor 24 from the plate or anodeelement I! to the plate or anode element 25 of the second half of thedriver tube ll. Similarly, the plate or anode element l6 of the secondhalf of the relay tube l2 connects to the control electrode or grid 26of the first half of this relay tube l2 by way of the resistor 21 and,as was the case with the connection of the plate or anode element is ofthe relay tub 12 to the plate or-anode element 25 of the driver tube H,the plate or anode element l6 of the second half of the relay tube I2connects to the plate or anode 23 of the first half of the driver tube ll by way of a similar conductor 29.

The cathode elements 30 of the relay tube l2 connect to ground 3| by wayof the cathode res'istor 32 and, similarly, a, leak resistor 33 isprovided between ground 3| and the control electrode 26 of the firsthalf of the tube, and, likewise, a leak resistor 34 connects betweenground 3| and the grid or control electrode 22 of the second half of therelay tube l2.

Connections to the driver tube l I from the relay tube l2 are also madeby way of the conductor 35 connecting the control electrode 26 of thefirst half of the relay tube [2 to the grid or control electrode 36 ofthe first half of the driver tube I I. This connection is made by way ofthe time constant circuit comprising the resistor element 31 and thecondenser 38, which condenser element 38 has one terminal connected toground 3| and'the other terminal connected both to the control electrode36 and to the lower end of the resistor 31. Similarly, the second halfof the relay tube l2 connects with the second half of the driver tube insuch a manner that the grid or control electrode 22 of the relay tube l2connects to the grid or control electrode 33 of the driver tube H by wayof a similar time constant circuit comprising the resistor 40 and acapacitor 41, which latter element also has one of its'terminalsconnected to ground 3| and the other terminal connected to the lower endof the resistor 40 and alsoto the control electrode 39.

assess:

Biasing voltage for the cathode elements 42 of the driver tube II isprovided by means of the resistor 43 connected by way of the conductor44 to the terminal l4, whereat high positive potential for the plate oranode elements of each of the relay and driver tubes I2 and II isprovided, so that normally the cathode elements 42 are biased positivelyrelative to ground 3| from the source connected to the terminal l4through the second biasing resistor 46 which connects to ground 3|.

Impulse potentials arranged for controlling the driver and relay unitare applied from an appropriate source (not shown) so connected at theterminal point 46 that the signals are applied by way of the condenser41 to control the tube ll. Thus, if the applied impulses are appliedwith negative polarity at the terminal point 46, the cathode elements 42of the driver tube II will be carried in the negative direction. Thewave representations shown adjacent the input terminal 46 and the outputterminals 20 and 2| are intended to represent schematically the generalform of the input and the output signals or waves in the system.

In the operation of the arrangement hereinabove disclosed, it is seenthat the tube arrangement I2 is essentially resistance coupled withmutual feedback provided by the resistors 23 and 34 on the one hand, and21 and 33 on the other hand, Consequently, it becomes apparent that thesystem is stable in only two conditions of operation and that is witheither the left half or the right half, also called the first half andthe second half, of the tube l2 cut oil respectively, so that at theplate or anode elements I5 and I6 only two levels of voltages areavailable, as are shown by the curves adjacent the output terminalpoints 23 and 2!.

If it is desired to drive this relay tube l2 by a series of appliedimpulses of substantially uniform polarity occurring at an arbitraryrepetition rate, this is then provided by means of the driver tube l Ito which the impulses shown adjacent the input terminal 46 are applied.

It can be seen that the two plate or anode elements 26 and 25 of thefirst and second halves of the driver tube I l are in parallel withopposite plate or anode elements l6 and i5, respectively, of the relaytube l2. The control electrodes 36 and 33 of the driver tube H are alsoin parallel with like control electrodes 26 and 22, respectively, of therelay tube, and are connected with this relay tube by way of theretardation or time constant circuits comprising the resistor 31 andcondenser 38 on the one hand, and the resistor 40 and the condenser 4|on the other hand. Therefore, in the stationary condition and in anon-operative state, the grid bias on the grids 36 and 26 and upon thegrids 33 and 22 are mutually identical, but by virtue of the applicationof positive biasto the cathode elements 42 from the source of positivevoltage connected to the terminal 14, this cathode is maintained atsufficiently high positive bias relative to the anode elements 28 and 25that both halves of the tube are cut off. Any controlling signal pulsesapplied from the input terminal point 46 by way of the condenser 41 andthe conductor 49 to the cathode elements 42 are intended, in thearrangement of Fig. 1, to be of negative polarity so as to overcome theeffect of the positive cathode. bias applied from the connection ofpositive voltage to the'source l4. If, now, an impulse of negativepolarity is applied to the input terminal 46, only one of the two halvesresistors the retardation or 1 ,ing action of the tube l pletelycancelled and the complete functioning preventing the-grid bias on the,onestate of operation amass? Y 3 of the driver tube II that is the halfin which the ing; such negative peaks are without objection. arid orcontrol electrode 8! or I! was of less negbut in some applications inthe arrangement of ative bias prior to the arrival of the impressed thesystem it is particularly desirable that the impulses, will give anegative and amplified plate current peak. If it is assumed, forinstance, that this is the left hand half or first half of the drivertube II, then it becomes apparent that the right hand half'of the tubeis left half of the relay tube blocked and that the I! also becomesconducting; with its right hand half also non-conducting-and the plateor anode element ll then at the higher positive voltage, level. as isindicated by the voltage curve appearing at the ter- 'I'his causes thena voltage peak minal point 2|. of negative polarity to appear acrossthe'resistor II, and this voltage peak is' transmitted back to the gridor control conducting half of electrode of the previously the relay tubeI! by the voltage divider arrangement provided byway of the 2! and I).Accordingly, the first 1 half of the-relay tube l2 willnow becomenon-con-- ducting with'the effect thatithe electronic relay 1 jumpsintothe other stable condition with the two triode sections changing in theoperational state.

g V .25 time delay" circuits provided ;-by the resistor 31 and thecondenser-[ll become'oi Under these circumstances itjwillbe seen thatimportance, as doesthe time delay circuit probecomes apparent at oncethat without'the in= vided' by the resistor so and the {condenser u. -f.It

instantaneously eil'ective on the grid orcontrol electrode 26 of' thetube r with the grid or control electrode fnectsto ground at ll.-iorming a part of the .designated in Fig. -2 as smaller than thecondenser shown in Fig. 1.

.clusion of the timedelay circuits, the'p'ot'entialj noted,particularly-in this connection,

negative peaks be avoided, so that the arrangement of Fig. 2 provides asuitable arrangement for accomplishing this aim and objective, and thisis" done through the use of two separate relay tubes III and II whichare of the tetrode or screen grid type. instead of the single relay tubedis- BI and I! respectively, rather asshown by Fig. l. It will be erallyspeaking, the connections from troi electrode 66 of: the

relay tube 60 is connected I 36 ofthe' driver tube II by way ofconductor and the time cone ,mnt circuit comprising'ithe-resistor- 11and the [condenser 38, which latter 'element-,also 'con- The condenserelement ime; constant circult is "(since it .is usually Y similarly, thecontrol'electrode I9 ofthe driver I? would be transmitted I withoutdelayto the grid or-control electrode 38. I of the tube I I, which'would forma 'sortof undee: sirable feedback with the result that the drive I wouldtend to be, comof the systemarrested in theabsenceof such' delay.- Thedelay circuits, however, take care of driving-tube ll V electrodes ofthe tubes fromchanging itsivalue forfthe duration pmhe :driving impulsesas impressed upon theterminal point 46. The delay circuit alsointrocliuiesa"de- I lay for'any change in'the grid'bias immediatelyefiective after the relay tubell hasshifted from to the other. should beunderstood that the delay circuit provided by either the resistor 31 andcondenser 36, 1

38 or the resistor 40 and condenser 4| was of the order ofmicro-seconds, so that it becomes apparent that the relay tube l2 willbe capable of following and performing extremely high frequency relayingaction while of course there is no low frequency limit on the output ofthe square waves.

Fig. 2, discloses a modification of the arrangement ofrFig. 1, and inthis figure, various common parts have like reference numerals.

From what has been explained, it is apparent that the arrangement ofFig. 1, while providing square waves of desired character, is generallyof the type where, in some instances, some sharp negative peaks mayoccur in the output due to the action of the driver stage. Generallyspeak- However, it

the time constant at the terminals to the cathode 42 pentode tube couldbe is shown by Fig. 3

tube I I connectswith the "grid or: control. electrade 6'! of the relaytube ll-fby way'oi'the conl and the time constant, circuit .comprisingthe resistor ill and the condenser 4|,

ductor 68 similar to the connection 'made' to the-control yelectrode'"of the tube 80.2;

. It will be seen, from the by Fig. 2, that suitable potentials for the"screen '80 and are provided by way of the voltage divider arrangement inthe 1 form of the resistors 89. 10,1! and 12, of which the latter isby-passedby a condenser I3, connected to receive energy from the sourceof potential connected between the terminals l4 and I4 and fed to supplyvoltages'for all Of the tubes Ii and by way of the conductor ll. Outputenergy from the relay tubes 80 and BI, is derived l'l' andlilrespectively. in accordance with the controlling impulses supplied ofthe driver tube ll by way .of suitable connections made at the terminalpoints 46 and-46'.

The high frequency response of the arrangement of Fig. 2 is, generallyspeaking, about twice that of the arrangement of Fig. 1 but, ascontrasted with the arrangement of Fig. 1, three separate tubes areincluded against the two tubes of the arrangement of Fig. 1, although atwin substituted for tubes 60 and 6|, if desired, withoutany substantialcircuit modifications.

In a further application of the arrangement of Fig. I particularly, amodification of the system where the square wave generator unit has beencombined with the cathode ray oscillograph device to enable an observerto view on the screen or target of the cathode ray tube, simultaneouslytwo waves which it is desired to observe. As shown by the arrangement ofFig. 3, the square wave generator comprising the driver tube ll and therelay tube 12 is substantially in accordance with the arrangement ofFig. 1, as are the time delay circuits comprising Pulses from thedriving tube ii are fed by wayof the conductors l2 and 63 to the theplate and output circuits or the plate ,to the screen and the-grid tothe grid ofthe tubes of Fig. 2 are reversed, as, compared to thearrangementofFlgJ. v I g f f In the arrangementoi Fig. 2, the gridor-conarrangement shown the plate. I and control electrode I09 4 theresistor-condenser combination 31-40 and In the arrangement shown byFig. 3, the transients to be observed will be produced on the screen ortarget (not shown) of the cathode ray tube conventionally represented as00. This tube includes the usual arrangement of the deflector platepairs 0I0I' and 02-02, herein shown as electrostatic plates fordeflecting the beam in two mutually perpendicular patterns. A conductivecoating forming the second anode 03 of the tube is connected to ground04 by way of the conductor shown. and one deflecting plate 0| of theplate pair lI-0I' is maintained at the resultant second anode voltage.The second anode element 03 is connected ahead of the first deflectingplate pair 0202. and next adjacent this anode element 03' is the firstanode 00. which is maintained at a suitable potential relative to thecathode 00 by means of the connection to the adjustable tap of thepotentiometer 00.

tube I02, and as was indicated in my above mentloned co-pendingapplication, a substantially linear saw-tooth voltage wave is thenadapted to appear across any of the selected capacity elements III whichmay be connected in circuit by the switching arm III, so that linearamplification of the developed saw-tooth voltage wave may be carried onin the amplifier tube III without distortion.

This connection of the output energy from the oscillator tube I02 to thecontrol electrode II2 of the amplifier tube I00 is provided by theindicated connection through the resistors Ill and The control electrode01 is connected adjacent Y the cathode emitter 00 and suitable controlpotentials for providing blanking, for instance, on the beam return pathor "snap-back are applied by way of the conductor 00 connected to thecontrol electrode on the one hand, and to the beam blanking controlmeans (later to be described herein) on the other hand. 7

At the terminal point 90 a, suitable source of negative potentialrelative to ground 04 is connected. This voltage source is provided forthe purpose of applying proper bias to the control electrode 31 at thesame time maintaining the cathode ata predetermined potential relativeto the first and second anode elements 05, 03' and 03 as indicated.

Deflection potentials for deflecting the beam developed within the tubein one of its two directions of deflection are provided by.the-conductorf2 and the capacity coupling 03, so that a connection is provideddirectly to the relay tube I2. A second connection by way ofthe'conductor 04 and the capacitor 95 is provided for supplying energyto the deflecting plate from the output or the amplifier tubes 80-01,later to be described. Similarly, deflection voltage from a deflectionvoltage generator is applied by way of the conductor 98 and the capacitycoupling 00 for deflecting the developed cathode ray beam in a directionmutually perpendicular to the direction of deflection provided by theplate pair 02-42.

Considering now the square wave generator unit comprising the drivertube. II and the relay tube I2, energy for driving this combination issupplied by way of the conductor IM and thecapacity 41- from adeflection voltage generator which is capable of producing suitabledriving impulses. erator is similar to that disclosed particularly by myco-pending application Serial No.*434,805, filed March 16, 1942, whereinthe sweep generator unit consists essentially of a blocking oscillatortube I02 and an amplifier tube I03, as explained in the last referred toco-pending application.

Generally speaking, there is provided in this arrangement a connectionfor a source of synchronizing impulses which may be provided by way ofthe terminal connection I04 and fed to the oscillator tube I02 by way ofthe condenser I05 and into the cathode circuit by way of the Thefeedback potentiometer connection I00. transformer I01 is connected, asshown, between 0! the H5 and the conductor IIB, as was explained in theaforesaid co-pending application. Suitable voltages for operating all ofthe tubes in the system are provided by the rectifier tube I20 connectedby way of the transformer l2I in known manner with the source of voltageapplied to the terminal points I22, which voltage source is preferablysuch that the supplied energy is fed to the transformer at the powersupply frequency of 60 cycles. Connected to the output of the rectifiertube I20 are two separate filter chains comprising the condenser andresistance filter combinations I23-I24 and I25-I28 respectively, atwhich the desired voltages are developed and across which condensersappear currents of pre- ,polarity so as to provide determined magnitude,it being appreciated that the current rating supplied by way of theconductor I! for the driver and relay tubes and the amplifiers 90 and 91is, generally speaking, higher than that supplied by way of theconductor I21 to energizethe oscillator and amplifier tubes I02 and I03.

In the oscillator combination, the energy developed across the plate oroutput resistor I20, which is connected with the plate coil of thetransformer I01 is, strictly speaking, of negative the impulses whichmay be fed by way of the connection IOI and the coupling condenser 41 tothe cathode 42 of the driver tube of the square wave generator. Theseimpulses occur at tive impulses, which occur at the saw-tooth fre- Yquency, are caused to appear in the conductor 09 which connects to thecontrol electrode 81 of the cathode ray tube, so that they can be usedto blank out the cathode ray during the 'eturn motion of its deflection,that is, during the snapback period while the beam is moving mostrapidly. The cathode ray tube control electrode 01 Generally speaking,this sweep genthus couples to the oscillator I02 by way of the conductor09 and the coupling condenser I30.

Output energy from the amplifier tube I00 is derived from the conductorI3I connected to the plate or anode element I32 of this tube, and

this is supplied by way of the coupling condenser 99 and conductor 90 todeflect the beam in the cathode ray tube by the application of potentialbetween the deflecting plate elements 0|. and 0|. The output energy fromthe relay tube I2 is supplied from the plate or anode element IE to thescreen electrode I33 of the first relay tube 96 by way of the condenserI34, and, similarly, the screen electrode I35 of the amplifier tube 91is energized through a coupling condenser I26 and the conductor I31 sothat it rethe saw-tooth frequency and thus trigger the driver tube-relaytube combinaceives energy output from the plate or anode II of the firsthalf of the relay tube I2.

At the same time that the energy output from the relay tube I2 is beingsupplied to the amplifler units 90 and 91, this output is also beingsupplied by way of the conductor 92, so as to control the verticalshitting or displacement or the wave traces produced upon theluminescent target or screen (not shown) of the cathode ray tube so thatsuccessive transients, as they appear upon the tube screen, shall beshifted or displaced rela-- tive to each other, and the rapiddeflection, as applied from the deflection unit comprising the tubes I02and I03, shall not follow successive identical traces, but rather beshifted laterally so that the arrangement becomes particularly usefulfor studying phenomena of time lag or relative phase shift between twosignals. It is, of

.course, evident that in such use the two "zero lines" are displaced,but, even so, this is desirable as it gives a better opportunity tocompare wave phenomena. For this purpose a suitable volume control isprovided in the form of the potentiometer I40 connected between theplate or anode elements I5 and I0 and the conductor 92 connected to theadjustable tap or this potentiometer.

at terminal points I44 and I45 alternately influence the deflectingelectrode 92'.

With the slider on potentiometer I40 in a midpoint position, as shown byFig. 3, the two produced transient tracings on the cathode ray tubev 90appear along the same axis. with the slider moved to the right or left,that is, toward the connection to anode or plate I5 or toward or to theconnection to anode or plate I6 will determine whether the transientstraced for the signals applied at terminals I44 and I45 shall be movedto a position above or below each other. In other words, the adjustmentof the tapping point on potentiometer I40 determines the relativedisplacement of the two transient tracings produced.

The circuit arrangement of Fig. 4 shows a still slightly furthermodification which is particularly adaptable for use where thecontrolling pulses are 01' positive polarity as contrasted with thenegative polarity pulse control shown by the arrangements of Figs. 1, 2and 3.

In the arrangement of Fig. 4, the input voltage is schematicallyrepresented as being the source I6I which connects between the terminalpoint I62 and ground I53 and feeds its energy by way I of the conductorsI64 and I65 through the cou- The energy output from the square wavegenerator and relay unit, as it is applied to'the amplifler tubes 99 and91 on the screen grid elements thereof, controls the amplification sothat there appears in the output conductor 94 connected to the plateelements I42 and I43 of the tubes 00 and 91 respectively,.suitableamplified energy and input signals applied to terminal points I44 andI45 respectively, which is controlled in accordance with whether or notthe first or the second half of the relay tube I2 is in operation, sothat one or the other of the tubes 95 and 91 will be amplifying thesignal energy impressed at the terminal points I44 and I45 whichrepresent the two transients to be observed through the applicationthereof to the deflecting plate element 92'. The impressed transientsare fed to the tubes 99 and 91 by way of the coupling condensers I45 andI41 respectively, so as to be applied between the control grids I 49 andI49 and the cathodes I50 and I5I respectively of these tubes by way orthe potentiometer connections I52 and I53, as shown.

The driver tube II, as above explained, controls the operation of therelay tube I2 so that onehalf of the relay tube or the other halfthereof is in a conductive state. Thus, with the plate members I5 and I6of relay tube I2 being connected to the grid electrodes I35 and I33 oftubes 91 and 90 it can be seen that one or the other of the last namedtubes is conducting in accordance with which of the relay tube halvesdraws current. The tubes 96 and 91 have their anode or plate elementsI42 and I43 connected to the source of positivevoltage in conductor I9through a common load resistor I 99'and these plate or anode elementslikewise connect to the deflecting electrode 82' through conductor 94and the coupling condenser 95. The input signals which represent the twotransients to be observed are continuously and independently applied atterminal points I44 and I45 and depending upon which of tubes 99 and 91conduct either of these transients is applied to the deflectingelectrode 02'. With the arrangement as disclosed the relay tube I2 is sotriggered that each half thereof draws current on every second cycle ofthe oscillator I02 and consequently the transients applied plingcondensers I81 and I50 of the delay circuit including the resistors I59and I10 respectively which connect to ground I63'by way oi the leakresistors Ill and I12. In this way, a positive pulse from the source I IBI is fed to the grid or control electrodes I12 and I13 respectively ofthe driver tube I14 which has its plate or anode elements I 15 and I15cross connected to the plate or anode elements I11 and I19 respectivelyof the relay tube I19 and, as above pointed out in connection with the.description of Fig. l, the grid or control electrodes I and I8I of therelay tube I19, in an inoperative state of the tubes I14 and I19, have apotential corresponding respectively to the grid or control electrodesI12 and I13 of the driver tube I14.

The arrangement, as it is disclosed by Fig. 4, provides that positivepotential for the plate or anode elements of the driver and relay tubesI14 and I19 may be applied at the terminal points I03 and I04, of whichthe latter is connected to ground, for instance, I53, and, accordingly,the positive voltage for the plate or anode elements of the tubes isapplied by way of the conductors I85 and I85 and the resistors I91 and I90. The resistors I99 and I respectively form, with the resistors I91and I98, a voltage divider by which suitable bias is applied to the gridor control electrodes I80 and I 0i of the relay tube I19.

For the purpose of applying a constant bias to the cathode element I9Iof the driver tube I14,

suitable bleeder resistors I92 and I93 are connected with the conductorI85 which carries the positive voltage from the source connected to theterminal I03, and the other terminal of these resistors connects, asindicated, to ground at I53, so that the cathode elements I9I have aconstant bias and the cathodes are blocked from ground by means of thecondenser element I94. Similarly, the cathodes I95 arebiased relative toground by means or the resistor I99, as indicated. i

Output energy from the system is derived at the terminals I91 and I99respectively, and the output voltages are, relatively speaking, asindicated by the wave forms immediately adjacent each output terminal.Similarly, the impressed input voltage is of the general natureindicated by the wave form adjacent the input source schematicallyrepresented as Iii.

The action of the circuit of Fig. 4, generally speaking, issubstantially like that explained in connection with Fig. 1, providedthe impedance of the source IGI is generally small as compared to theleakage of the resistors I69 and H0, which are preferably of the generalorder of one megohm.

Further, generally speaking, the arrangement of Fig. 4 is so constitutedthat the power taken from the source is usually less than explained inconnection with the modification of Fig. 1, and similarly, the reactionof the system upon the source is also generally reduced.

A still further advantage of the arrangement of Fig. 4 is that it ispossible, in this connection, to take advantage of the gain provided bythe driver tube ill, with the result that the system has an increasedvoltage sensitivity which enables it to respond fully to input andcontrolling pulses which are of lesser magnitude, generally speaking,than those applied with the system of Fig. 1, wherein the control isunder the influence of negative pulses.

It is, of course, apparent that many and other modifications may be madein this system without departing from the spirit and scope or theforegoing disclosure, and therefore I believe myself to be entitled tomake and use any and all of these modifications which fall fairly withinthe spirit and scope of the invention and the hereto appended claims.

What I claim is:

1. A signalling circuit including thermionic driver tube means whichinclude a first and a second independent electron path and whereincollector and control electrode means are included in each path,thermionic relay tube means which include a first and a secondindependent electron path and wherein collector and control electrodemeans are also included in each path, means to parallelly connect thecontrol electrode means of the first path of the driver and relay meansand to similarly connect the control electrode means of the secondelectron paths of said driver and relay means, means to connect thecollector electrode means of the first electron path of the driver andthe second electron path of the relay tube and to similarly connect thecol lector electrode means of the second path of the driver means andthe first path of the relay means, a time delay circuit included in theconnection between the parallelly connected control electrode means ofeach paths, and terminal means for applying impulse signals to thethermionic driver means, and terminal means for deriving output energyfrom the thermionic relay means.

2. An electron tube circuit including thermionic driver tube means whichcomprise a first and a second independent electron path and whereincollector and control electrode means are included in each path,thermionic relay tube means which include a first and a secondindependent electron path and wherein collector and control electrodemeans are also included in each path, means to parallelly connect thecontrol electrode means of the first electron paths of the driver tubeand relay tube means and to similarly connect the second electron pathsof said driver tube and relay tube means, means to connect the collectorelectrode means of the first electron path of the driver tube means andthe second electron of the driver and relay:

path of the relay tube means and to similarly connect the collectorelectrode means of the second path of the driver means and the firstpath of the relay means, impedance means included in the connectionbetween each of the said parallelly connected control electrode means oreach of the driver and relay paths, terminalmeans for applyingcontrolling impulse signals to the said driver tube means, and terminalmeans for deriving output energy from the said relay tube means.

3. A signal keying circuit including thermionic driver tube means whichinclude a first and a second independent electron path and whereincollector and control electrode means are included.

in each path, thermionic relay tube means which include a first and asecond independent electron path and wherein collector and controlelectrode means are also included in each path, means to parallellyconnect the control electrode means of the first electron paths of thedriver means and relay means and to similarly connect the secondelectron paths of said driver means and said relay means, means toconnect the collector electrode means of the first electron path of thedriver means and the second electron path of the relay means and tosimilarly connect the collector electrode means of the second path ofthe driver means and the first path of the relay means, terminal meansfor applying impulse signals to the driver tube means to initiate anelectron flow in one of the said electron paths thereof and therebycontrol an electron flow in one of the electron paths of the relay tubemeans, time delay means included in the interconnection of the controlelectrode means between the driver and relay means, said time delaymeans being adapted to control the rate at which the conductivityconditions of the alternate electron paths of said driver tube are ableto follow changes in conductivity of the said relay means, and terminalmeans for deriving output energy from the relay means.

4. A signalling circuit including thermionic driver tube means whichinclude a first and a second independent electron path and wherein acollector means, a control electrode means and a cathode are included ineach path, thermionic relay tube means which include a first and asecond independent electron pathand wherein a collector means, acontrolelectrode means'and a cathode are also included in each path,means to parallelly connect the control electrode means of the firstpath of the driver and relay means and to similarly connect the controlelectrode means of the second electron path of said driver and relaymeans, means to connect the collector electrode means of the firstelectron path of the driver and the second electron path of the relaytube and to similarly connect the collector electrode means of thesecond path of the driver means and the first path of the relay means,

means to connect all of the cathodes to a common point of fixedpotential, a pair of time delay circuits each including a seriesresistor and condenser combination, the resistor element of said timedelay circuits being included in the connection between the parallellyconnected control electrode means of each of the driver and relay pathsand the condensers of said circuits being connected between the drivertube means control electrodes and the said point of fixed potential,terminal means for applying impulse signals to the control electrode tocathode circuit of each 15 electron path of the driver tube means, andterrections of deflection,

minal means for deriving output energy from the thermionic relay means.

5. A signalling circuit including thermionic driver tube means whichinclude a first and a second independent electron path and wherein anelectron emitter, a collector electrode and control electrode means areincluded in each path,

thermionic relay tube means which include a first I and a secondindependent electron path 'and wherein an electron emitter and aplurality of cold electrode means are also included in each path, meansto parallelly connect the control electrode means of the first electronpath of the driver tube means and one of the cold electrodes of therelay tube means, and means to similarly connect the control electrodemeans of the second electron paths of said driver tube means and a coldelectrode of the relay tube means corresponding to that connected in thefirst parallel connection, means to connect the collector electrodemeans of the first electron path of the driver and an independent coldelectrode of one of the electron paths of the relay tube means and tosimilarly connect the collector electrode means of the second path ofthe driver means and an independent cold electrode in the other electronpath of the relay means, means to connect all of the electron emitterelectrode to a point of substantially constant potential, a pair of timedelay circuits having one element connected to the point of fixedpotential, said delay circuits each being included in the connectionbetween the control electrode of the driver means and the said connectedcold electrodes of the relay means, terminal means for applying impulsesignals to the said thermionic driver means, and terminal means forderiving output energy from the thermionic relay means.

6. Cathode ray oscillograph apparatus comprising a cathode ray tubehaving means included therein for developing a cathode ray beam and atarget upon which the cathode ray beam is adapted to impinge to producea record, electrode means for deflecting the cathode ray beam in twodirections each substantially normal with respect to the other,commutating means comprising thermionic driver tube means and thermionicrelay tube means, said driver tube means including a first electron pathand a second independent electron path and having a collector electrodemeans and a control electrode means included in each of said paths, andsaid relay tube means also including a first electron path and a secondindependent electron path and having a collector electrode means and acontrol electrode means included in each of said paths, means forparallelly connecting the control electrode means of the first electronpaths of each of the driver means and the relay means and to similarlyconnect the control electrode means of the second electron paths of eachof said driver means and said relay means, means to connect thecollector electrode means of the first electron path of the driver meansand the collector electrode means of the second electron path of therelay means and to similarly connect the collector electrode means ofthe second path of the driver means and the collector electrode means ofthe first electron path of the relay means, impedance means included inthe connection between each of the said connected control electrodemeans of the driver and relay means, a deflection generator fordeveloping substantially sawtooth wave formations connected to deflectthe electron beam of the cathode ray tube in one oi its two dimeans forenergizing the driver tube means of the commutator with impulses at afrequency corresponding to the sawtooth frequency generated by saiddeflection generator means. means for deriving from the relay means ofsaid commutator pulse energy of alternating positive and negativepolarity from the collector electrode means of the said relay means, andmeans for biasing the other of said deflecting means by said pulseenergy alternately, and means responsive to the output of the said relaymean for applying a multiplicity of transients for observationalternately to the said last named deflecting means.

7. The system claimed in claim 6 comprising, in addition, a plurality ofamplifying means to which independent transient signals are applied, andmeans for rendering said amplifier tubes operative and inoperative underthe control of the output energy from said relay means, and means forapplying, the triggering impulses supplied to the said driver tube alsoto control the beam production within the cathode ray tube.

8. Cathode ray oscillograph apparatus comprising a cathode ray tubehaving means included therein for developing and modulating acathode raybeam, and a target element upon which the said cathode ray beam isadapted to impinge, a pair of deflecting electrode means for deflectingthe developed cathode ray beam relative to the target in two mutuallyperpendicular directions, a plurality of terminal connections forconnecting to a plurality of signal circuits-electron tube amplifiersconnected to receive energy from each terminal connection, said electrontube amplifiers having a common output circuit and means for connectingone of the pair of beam deflecting means to the said common outputcircuit, a sweep generator means for developing substantially saw-toothwave energy,'means for applying saidsaw-tooth wave energy to the secondof said pair of beam deflecting means, a commutating means comprising adriver tube means and a relay tube mean said driver tube and relay tubemeans each including a first and a second independent electron path withcontrol electrode means and collector electrode means included in eachpath, means for parallelly connecting the control electrode means of thefirst electron paths of each of said driver and said relay means and forsimilarly connecting the control electrode means of the second electronpaths of each of said driver and said relay means, mean to connect thecollector electrode means of the first electron path of the driver meansand the collector electrode means of the second electron path of therelay means and to similarly connect the collector electrode means ofthe second electron path of the driver means and the collector electrodemeans of the first electron path of the relay means, a time constantcircuit included as a part of the connection between the said collectorelectrode means of the said driver to relay paths, means for developingpulse energy at a frequency corresponding to the frequency of the saidsweep circuit generator, connection means for simultaneously applyingsaiddeveloped pulse energy to trigger the electron paths of the drivertube means and simultaneously to suppress instantaneously the developedelectron beam in the said tube, means for developing from the separateelectron paths of the relay tube means energy alternately varyingbetween minimum and maximum values, connection means for supplying saidenergy to the said amplifiers for alteralternate wave traces are natelyrendering the independent amplifiers operative and inoperative at a ratecoinciding with the rate at which pulse energy is developed, and asecond connection for simultaneously biasing the deflecting electrodemeans to which the transient signals are applied by fixed amounts, sothat displaced one from the other by predetermined amounts.

9. Cathode ray oscillograph apparatus comprising a cathode ray tubehaving means included therein for developing and modulating a cathoderay beam and a target element upon which the said cathode ray beam isadapted to impinge, a pair of deflecting electrode means for deflectingthe developed cathode ray beam relative to the target in two mutuallyperpendicular directions, a plurality of terminal connections forconnecting to a plurality of signal sources, electron tube amplifiermeans connected to receive energy from each terminal connection, saidelectron tube amplifiers having a common output circuit and means forenergizing one of the pair of beam deflecting means to the said commonoutput circuit for deflecting the developed cathode ray beam in one ofits directions of traverse of the target under the control of the signaloutput from the said amplifiers, a sweep generator means for developingsubstantially saw-tooth wave energy, and means for applying saidsaw-tooth wave energy to the second of said pair of beam deflectingmeans for deflecting said beam along a timing axis in a directionmutually perpendicular to the direction of deflection initiated by theoutput energy from said amplifiers, a commutating means comprising adriver tube means and a relay tube means, said driver tube and relaytube means each including a first and a second independent electron pathwith control electrode means and collector electrode means included ineach path, means for parallelly connecting the control electrode meansof the first electron paths of each of said driver and said relay meansand for similarly connecting the control electrode mean of the secondelectron paths of each of said driver and said relay means, means toconnect the collector electrode means of the first electron path of thedriver means and the collector electrode means of the second electronpath of the relay means and to similarly connect the collector electrodemeans of the second electron path of the driver means and the collectorelectrode means of the first electron path of the relay means, a timeconstant circuit included as a part of the connection between the saidcollector electrode means of the said driver to relay paths, means fordeveloping pulse energy at a frequency corresponding to the frequency ofthe said sweep circuit generator, connection means for simultaneouslyapplying said developed pulse energy to trigger one or the other of theelectron paths of thedriver tube means and simultaneously to suppressinstantaneously the developed electron beam in the said tube, means fordeveloping from the sep arate electron paths of the relay tube meansenergy alternately varying between minimum and maximum values,connection means for supplying said energy from the relay to key thesaid amplifiers and alternately rendering the independent amplifiersoperative and inoperative at a rate coinciding with the rate at whichpulse energy is developed, and a second connection means forsimultaneously supplying the relay output energy to the deflecting meansto provide a bias whereby alternate wave traces are displaced one fromthe other by predetermined amounts.

10. Cathode ray oscillograph apparatus comprising a cathode ray tubehaving means included therein for developing and modulating a cathoderay beam and a target element upon which the said cathode ray beam isadapted to impinge, a pair of deflecting electrode means for deflectingthe developed cathode ray beam relative to the target in two mutuallyperpendicular directions, a plurality of terminal connections forconnectin to a plurality of transient signal circuits, an electron tubeamplifier connected to receive energy from each terminal connection,said electron tube amplifiers having a common output circuit and meansfor connecting one of the pair of beam defleeting means to the saidcommon output circuit, a sweep circuit generator means for developingsubstantially saw-tooth wave energy, and means for applying saidsaw-tooth wave energy to the second of said pair of beam deflectingmeans, a commutating means comprising a frequency dividing and switchingamplifier tube means, mean for developing pulse energy at a frequencycorresponding to the saw-tooth fre- I quency generated by the said sweepcircuit generator, connection means for simultaneously applying saiddeveloped pulse energy to trigger the frequency dividing and switchingamplifier tube means and to suppress instantaneously the developedelectron beam in the said tube, and connection means for supplyingoutput energy from the said frequency dividing and switching amplifierto alternately render the independent transient signal amplifiersoperative and inoperative at a rate corresponding to half that of thesawtooth energy, and a second connection for simultaneously biasing byflxed amounts the deflecting electrode means to which the transientsignals are applied so that alternate wave traces are displaced one fromthe other.

11. Cathode ray oscillograph apparatus comprising a cathode ray tubehaving means included therein for developing and modulating a cathode rabeam and a target element upon which the said cathode ray beam isadapted to impinge, a pair of deflecting electrode means for deflectingthe developed cathode ray beam relative to the target in two mutuallyperpendicular directions, a plurality of terminal connections forconnecting to a plurality of transient signal circuits, an electron tubeamplifier connected to receive energy from each terminal connection,said electron tube amplifiers having a common output circuit and meansfor connecting one of the pair means and to suppress instantaneously thede-,

veloped electron beam in the said tube, connection means for supplyingoutput energy from the said frequency dividing and switching amplifierto alternately render the independent transient signal amplifiersoperative and inoperative at a rate corresponding to half. that of thesaw-tooth energy, a second connection for simultaneously biasing byfixed amounts the deflecting electrode means to which the transientsignals are applied so that alternate wave traces are displaced one fromthe other, and means to initiate each alternate scanning cycle at a liketime in the scanning cycle of the timing axis path.

12. Cathode ray oscillograph apparatus comprising a cathode ray tubehaving means included therein for developing and modulating a cathoderay beam and a target element upon which the said cathode ray beam isadapted to impinge, a pair of deflecting electrode means for deflectingthe developed cathode ray beam relative to the target in two mutuallyperpendicular directions, a plurality of terminal connections forconnecting to a plurality of transient signal circuits, an electron tubeamplifier connected to receive energy from each terminal connection,said electron tube amplifiers having a common output circuit and meansfor connecting one of the pair of beam deflecting means to the saidcommon output circuit, a sweep circuit generator means for developingsubstantially saw-tooth wave energy, and means for applying saidsawtooth wave energy to the second of said pair of beam deflectingmeans, a commutating means comprising a frequency dividin and switchingamplifier tube means, means for developing pulse energy at a frequencycorresponding to the sawtooth irequency generated by the said sweep circuit generator, connection means for simultaneously applying saiddeveloped pulse energy to trigger the frequency dividing and switchingamplifier tube means and to suppress instantaneously the developedelectron beam in the said i tube, connection means for supplying outputenergy from the said frequency dividing and switching amplifier toalternately render the independent transient signal amplifiers operativeand inoperative at a rate corresponding to half that of the saw-toothene gy, a second connection for simultaneously biasing by fixed amountsthe deflecting electrode means to which the transient signals areapplied so that alternate wave traces are displaced one from the other,and means for interlocking the switching and timing of the defiectionpaths to align the successive wave traces with regard to each other.

13. A signalling circuit including thermionic driver tube means whichinclude a first and a second independent electron path and whereincollector and control electrode means are included in each path,thermionic relay tube means which include a first and a secondindependent electron path and wherein a collector, a control electrode,and at least a screen electrode means are also included in each path,means to parallelly connect the control electrode means of the firstpath of the driver and the relay means and to similarly connect thecontrol electrode means of the second electron paths of the said driverand relay means, means to connect the collector electrode means of thefirst electron path of the driver and the screen electrode element ofthe first electron path of the relay tube means and to similarly connectthe collector electrode means of the second path of the driver means andthe second path of the relay'means, a time delay circuit includedin theconnection between the parallelly'connected control electrode means ofeach of the driver and relay paths, terminal means for applying impulsesignals to the thermionic driver means, and terminal means for derivingoutput energy from the thermionic relay means.

KURT SCHLESINGER.

